M5R2 (M5OD-R2) Rebuild Deep Dive

[97Sandbox]

Lowered 4wds are dominating the drag strips… just sayin these days a 4wd f150 is faster then a mustang due to traction

Just ask Tim our Canadian lowered 4wd sport drag racing neighbor

It is tempting...especially since I have all the driveline parts I'd need. I'd need a different front coilover setup to clear axles though. Maybe someday!

Looking at that chart, my guess is that it was a Mitsubishi FM146 transmission.

 

[97Sandbox]

0.010 shim made and installed.

Clearance is now measuring between 0.011 and 0.015, so I'm calling it in-spec on average.

Rear bearings and lock nuts installed.

I'm going to need the missus to help hold the case while I torque them. Then they get staked in.

Removed the rubber rear shift rail plugs and punched the pins out of the 1/2 and 3/4 rails.

You have to slide the 3/4 fork off to get the 1/2 fork off. The less-used 1/2 fork was installed in place of the old one, then everything went back where it was.

Make sure you get everything back to neutral (position shown in both pictures above) or you'll be confused and/or sorry come reassembly time.

I went ahead and installed the new cover gasket, steel shift rail plugs, and new shifter bushings and dust cover.

We're in the home stretch now!

 

[97Sandbox]

Middle of the torque spec for countershaft nut is about 120ft-lb, not too bad. It's a 32mm nut.

The middle of the spec for the output lock nut is more like 180ft-lb...my big torque wrench only goes to 150. My plan was to go to 150 then give it another grunt of a turn. Fun fact: you can almost use a 4.0 fan clutch holding tool as a crows foot for the lock nut. I say almost because it's a bit too big. It'll be fine to drive the nut most of the way down, but when the torque gets high enough, it wants to slip. And slipping when you're pushing down with all your body weight isn't fun. I managed not to punch the ground with my wrench-holding hand, but I dislocated my shoulder on the side I was holding the case with. My wife was too grossed out, so I had to pop it back in myself haha. I've done that once before when I crashed my bike and I'm sure it's going to be sore for a couple weeks...

Ultimately, I snugged down my largest adjustable wrench and stood on it. I weigh ~195 and the wrench handle is a little longer than a foot, so I'm calling the nut torqued to spec.

Time to stake the nuts, then clean and seal the tail housing.

 

[410Fortune]

Holy crap dude… ouch
Tumeric helps with inflammation hahahahhahahahaha oh man

Nice work! Yes that nut is now torqued

Torque spec on our cv axle nuts is 220 ft lbs
I’m like 190-200 lb
I don’t use a torque wrench over 120 I just use me and my ability to push and pull on levers… never had an issue
We call it “tight as ****”

 

[97Sandbox]

Haha yeah that's how I've always done axle nuts too and I need to stick with that technique from now on. The spec for my old Civic axles was over 300ft-lb -- have to stand on the handle of a breaker bar for that kind of torque!

 

[97Sandbox]

It's all back together. Shift linkage and modified harness included.

Tomorrow it goes back in. And of course transfer case, exhaust, and drive shafts. And interior stuff too. But I cannot wait to drive this thing!

Then I'll rebuild the 2wd and we can see what's different.

 

[97Sandbox]

Holy cow, I just had such a hard time getting this transmission back in. Way harder than the first time I installed it. I think the issue was that there was one dowel left in the block and one dowel left in the bell housing. Trying to get everything lined up with a fairly wavy block separator plate in between was not fun.

I'm going to make sure to punch the dowels out of my 2wd transmission and just leave them in the block next go around. That'll keep the separator plate in the right spot.

 

[410Fortune]

Duct tape for the plate
If it fights you take a break come back at it, usually slides right in
A truck with the 5 speeds is small circles
Once you get the input shaft through the clutch and pressing the case towards the bellhousing you make small circles with the tailhousing… then it slides right together

The dowls are pita
The scatter shield doesn’t like to stay put!
A small tab of duct tape will hold the plate in place while you play trans installer

Good job and thanks again

 

[97Sandbox]

When I drill my 2wd bell housing for the 7/16" bolts, I'm going to drill a hole so I can punch out the right side dowel. The left dowel is already accessible from the back and easy to punch through.

I agree with the circles technique. My trans was a little crooked on top of the jack so the circling was the only way to jiggle those dowels in even though the input shaft was already through the clutch and into the pilot bearing.

 

[97Sandbox]

Test drive complete! The transmission definitely feels way better shifting between gears and there's no more clunky input shaft noise. It's still not super smooth into first or reverse, so I'm guessing there's still air in my clutch hydraulic line.

What's the preferred bleed technique for these? I've tried gravity and power bleeding, pulling the piston from the master to "burp" it, and vacuum bleeding from the reservoir and none of them seemed to make a difference. I know these are notorious for trapping bubbles, but there's got to be some way, right?

 

[410Fortune]

I hang the master cylinder and line on the wall vertical
Tap whole assembly with screwdriver wrap on that sucker

Tiny air bubbles will come out forever! Once in a while a pea size one
Activate the plunger best you can (Phillips) while wrapping on it … tiny bubbles

Once no more air for quite a while
Install in truxk
Bleed slave 3-4 times
Done

When bleeding slave I crack bleeder close it quickly
Helper (or stick between pedal and aeat lol) should have pedal all the way to floor when you crack it

The method you did of removing the e clip and plunger in the car should have released any trapped air… but even the smallest bubbles can stop it from fully releasing

They seem to get trapped in the brass fitting that connects line to master, they get trapped in the line and they get trapped in the master. The master cylinder has a notorious high spot in it where a bubble can seriously be stuck…. The best way to remove that one is how you did.. in the car.. but it may have gathered there again… all those other little bubbles will in time all gather at the top of the plunger and create this issue again… trapped pea size bubble at top of master cylinder

Tapping is the key to moving that bubble

The bubbles (tiny) get trapped in the quick connect fitting on the trans side of the line!!
Pita to bleed
I have not had issue since I found the hang it on the wall method and wrap on it for the next hour technique (thanks YouTube)

I have shimmed a slave cylinder a time or two
It is possible to put washers behind it
Shouldn’t have to do that

Good job! Working slush box! I’m jealous

 

[97Sandbox]

I did the hang and tap method before install when I first did the manual swap -- would you actually pull the line out after install and do it again?

I may just power bleed to try to get any bubbles forced out of the quick connect and slave, then pull the piston out of the master and try to get any air out of there. And tap the line a lot along the way.